This invention relates to an improved collection and transfer device for collecting, transferring, and filtering a medical sample.
There are a number of applications, usually medical, in which solid particles are extracted from a liquid or slurry. The particles to be examined may be captured by a filter or may be passed by the filter while larger, undesired particles are blocked. One specific medical application includes the separation of parasite larva and eggs from a stool sample placed in a specimen vial or a collection container filled with a fixative or preservative. The devices used for this application are typically called xe2x80x9cstool transportation and filtration systems.xe2x80x9d One improvement over previous devices is discussed in U.S. Pat. No. 4,675,110 assigned to the same entity as this application. In that device, one improvement involved the equalization of pressure between a collection vessel and an attached receptacle vessel. Another improvement is discussed in U.S. Pat. No. 5,624,554 also assigned to the same entity as this application. Both of these patents are hereby incorporated herein.
There are other devices on the market for collecting and filtering such samples but many do not offer a safe, closed system in which collection and transfer occurs without any chance of spillage. Some devices spill easily, others include filters susceptible to blockage, and still others require additional components in order to collect and agitate a sample or will only work properly with specially fabricated components. Many are difficult to use and may confuse laboratory technicians or worse, the patient.
In the simplest example, the patient places a stool sample in a collection container filled with a fixative, seals the collection container and then brings it or sends it to a laboratory. The laboratory technician then shakes the collection container to agitate the sample, slowly opens the collection container to prevent the sample from being forcefully ejected under pressure from the collection container, and then pours the sample into a funnel fitted with gauze to filter the sample before it is received in a centrifuge tube.
When this process is repeated multiple times in a given work day, it quickly becomes a complex, messy, and inconvenient process.
It is therefore an object of this invention to provide a collection and transfer system which is more universal in design.
It is a further object of this invention to provide such a collection and transfer system which is simple to use.
It is a further object of this invention to provide such a collection and transfer system which eliminates the potential for spillage associated with many prior art collection and transfer systems.
It is a further object of this invention to provide such a collection and transfer system which overcomes the inconvenience associated with some prior art collection and transfer systems.
It is a further object of this invention of this invention to provide such a collection and transfer system which overcomes the problem of limited functionality associated with certain prior art collection and transfer systems.
The invention results from the realization that complexity, mess, inconvenience, and limited functionality associated with some prior art collection systems can be overcome by a transfer device which mates on one end with and includes a needle for piercing the bottom of a collection container and which mates on the other end with different size centrifuge tubes to transfer a specimen from the bottom of the collection container or any collection vials through the needle and into the centrifuge tube. This invention results from the further realization that the specimen can be pre-filtered and agitated while it is still in the collection container by including a filter element with agitating vanes in the collection container itself.
This invention features a universal collection and transfer system. The primary components typically include a collection container with an open upper end, a filter which divides the container into upper and lower sections, an agitator, and a closed bottom with a piercable portion. Also included is a transfer device including a slender hollow shaft for piercing the piercable portion of the bottom of the collection container in order to hygienically transfer a filtered sample from the collection container to a second container. The agitator may include a plurality of vanes upstanding from the filter. Preferably, the collection container includes a wall extending from the bottom thereof defining a chamber for receiving the transfer device therein. The closed bottom of the collection container is typically funnel shaped and terminates in the piercable portion. The filter may be disposed over the top of the funnel shaped bottom. Then, the transfer device includes a concave wall surrounding the shaft which mates with the funnel shaped bottom of the collection container to align the shaft with the pierceable portion of the bottom of the collection container.
The transfer device may further include further an opening in the bottom thereof defining a chamber of receiving the second container. A tube may be located in the opening in fluid communication with the hollow shaft. One or more vents may be provided in the transfer device for relieving pressure in the second container.
The collection container is typically made of a plastic material and has side walls which can be deflected inward to force the filtered sample out of the collection container, through the transfer device, and into the second container. The transfer device is also typically made of a plastic material. In many embodiments, the second container is a centrifuge tube.
A universal collection and transfer system according to this invention includes a collection container, a second container, and a transfer device mateable with both the collection container and the second container and including a hollow shaft which pierces the collection container to transfer a sample in the collection container into the second container. A collection container in accordance with this invention has an open upper end, a filter which divides the container into upper and lower sections, an agitator, and a closed bottom with a pierceable portion.